Appendix C

Information for Proposers Regarding Proposal Submission,

Evaluation, Selection, and Implementation

C.1 Proposal Preparation and Submission

C.1.1 General Observing Parameters

The current Announcement covers the 12 months of observations to be
carried out with RXTE beginning on or around March 1, 2002. These
observations will be selected from proposals submitted to NASA in
response to this Announcement.

Once the targets to be observed are identified, the Science Operations Center
(SOC) is responsible for generating the science time-line under the specified
constraints. Under normal operating conditions, the only constraint is the
angle between the target and the Sun, which must be larger than 30 degrees.
Proposers may specify additional constraints on their observation. Maneuvers
are scheduled to occur during passage of the spacecraft through the South
Atlantic Anomaly (SAA) or, where possible, when the target is occulted by the
Earth. Large maneuvers occur at ~6 degrees per minute, and a typical
maneuver between unrelated targets incurs approximately 500 seconds of
overhead. Approximately 20 maneuvers per day can be performed. These values
may change as a result of further in-orbit experience. Scans of extended
targets can be made at lower slew rates.
There are no restrictions regarding the maximum amount of observing
time or the maximum number of targets that may be requested. Proposals
must have at least one target, and every observation must be a minimum
of 1000 seconds in duration.

Proposals may be submitted for single targets with short or long observation
times, or for larger programs involving multiple targets or significant amounts
of observing time. All proposals will be reviewed in the same peer
review, which should result in the selection of a mix of large, medium,
and small programs. However,
Cycle 7 proposers are specifically encouraged to consider projects that
would profit uniquely from large amounts of observing time, to enable
investigations of significantly greater scope than those possible in
the first four RXTE observing cycles. Accordingly, large proposals,
defined as those that request observing times of 500 ksec or more, will
be given special consideration and are allowed 6 pages for the
Scientific Problem and Technical Feasibility section of the proposal
(see Appendix C.2.2.2).

There are no specified key projects for RXTE. Proposers may request
observations extending beyond the end of the formal 12-month period covered by
this Announcement, but must present compelling scientific justification for such
observations. For the current observing cycle, it is anticipated that
observing time will be awarded to about 100 proposals.

RXTE can respond quickly to the transient behavior of astronomical
sources, so the exact scheduling of time-critical observations may be
done only a few days or weeks prior to the observation. One of the
primary design criteria for RXTE was the rapid response to Targets of
Opportunity (TOO's). Proposals to observe TOO's are allowed under
this Announcement. Such observations can be triggered either by a
change in flux as measured by the ASM, or by optical, radio, or other
external triggers. The automatic SOC software may detect some critical
changes of ASM flux, however, it is the responsibility of the PI to
monitor the behavior of the source of interest using the online ASM
light curves. For external triggers, it is the responsibility of the
Principal Investigator to notify the SOC that the triggering event has
occurred. When a TOO is triggered and approved by the RXTE Project
Scientist, a repointing of the satellite can be effected in as short a
time as seven hours from the time of notification. Data rights from a
TOO proposal that has been peer reviewed and approved in response to
this Announcement are identical to those of a non-TOO proposal that
has been peer reviewed and approved in response to this Announcement.
Further details on proposing for observations of
Targets of Opportunity can be found in
the RXTE Technical Description.
Prospective proposers should note that reductions in
staffing resources may affect the capability of the SOF to respond to
TOO's under some circumstances. Accepted TOO proposals will be
carried out as proposed on a best efforts basis.

One advantage of this mission in comparison to previous missions is the
relatively unconstrained solar angle constraint that makes available
approximately 93% of the sky at any given time. The large sky accessibility
affords an opportunity for coordinated ground-based and RXTE observing, as a
given target can be scheduled for observations during night-time hours at
ground-based telescopes. Up to 4 coordinated observations per month will be
designated for "special handling" by the peer review panel. Observations with
this designation will be assigned a high priority for matching the requested
coordinated observing times. There is no limit on the proportion of
observations that can be accepted that include time, phase, or other observing
constraints.

C.1.2 Who May Propose

Proposals may be accepted from any institution within or outside the United
States. RXTE proposals must identify a Principal Investigator (PI), who
assumes full responsibility for the conduct of the scientific
investigation.

Following selection, the SOC will communicate only with the person identified
as PI or lead Co-Investigator (Co-I), who can also serve in this role in the
event that the PI is unavailable. It will be the PI's responsibility to
respond to any questions concerning observational constraints or
configurations.

C.1.3 Who May Propose -- Foreign Participation

NASA welcomes proposals from outside the U.S..
Proposals from outside the
U.S. and U.S. proposals that include non-U.S. participation must be endorsed by
the respective government agency or funding/sponsoring institution in the
country from which the non-U.S. participant is proposing. Such endorsement
should indicate that the proposal merits careful consideration by NASA
and that, if the proposal is selected, sufficient funds will be made
available to undertake the activity as proposed.

All proposals must be typewritten in English and comply with all other
submission requirements stated in the Solicitation Announcement.
All non-U.S. proposals will
undergo the same evaluation and selection process as those originating in the
U.S. All proposals must be received before the established closing date; those
received after the closing date will be held for the next proposal cycle.
Sponsoring non-U.S. agencies may, in exceptional situations, forward a proposal
without endorsement to the submission address if endorsement is not possible
before the announced closing date. In such cases, however, NASA's
Office of Space Science should be advised when a
decision on endorsement can be expected.

Successful and unsuccessful proposers will be contacted directly by the NASA
Office of Space Science. Copies of the letters of notification
will be sent to the sponsoring government agency. Should a foreign proposal
or a U.S. proposal with non-U.S. participation be selected, NASA's
Space Science and Aeronautics Division will arrange with the foreign
sponsor for the proposed participation on a no-exchange-of-funds
basis, in which NASA and the non-U.S. sponsoring agency will each bear the cost
of discharging their respective responsibilities.

Depending on the nature and
extent of the proposed cooperation, these arrangements may entail:

an exchange of letters between NASA and the foreign sponsor; or

a formal Agency-to-Agency Memorandum of Understanding (MOU).

C.1.4 Export Control Guidelines Applicable to Foreign Proposals
and Proposals Including Foreign Participation

Foreign proposals and proposals including foreign participation
must include a section discussing compliance with U.S. export laws
and regulations, e.g. 22 CFR Parts 120-130 and 15 CFR Parts 730-774,
as applicable to the circumstances surrounding the particular foreign
participation. The discussion must describe in detail the proposed
foreign participation and is to include, but not be limited to,
whether or not the foreign participation may require the prospective
proposer to obtain the prior approval of the Department of State or
the Department of Commerce via a technical assistance agreement or an
export license, or whether a license exemption/exception may apply. If
prior approvals via licenses are necessary, discuss whether the
license has been applied for or if not, the projected timing of the
application and any implications for the schedule. Information
regarding U.S. export regulations is available at
http://www.pmdtc.org/
and
http://www.bxa.doc.gov/. Proposers
are advised that under U.S. law and regulations, spacecraft and their
specifically designed, modified, or configured systems, components and
parts are generally considered "Defense Articles" on the United States
Munitions List and subject to the provisions of the International
Traffic in Arms Regulations (ITAR), 22 CFR Parts 120-130.

C.2 Proposal Format and Content

C.2.1 Overview

In the proposal review, the scientific and
technical merits of the proposed investigation will be reviewed, including the
appropriateness of using RXTE to address the scientific objectives and its
relevance to furthering our understanding of high energy astrophysical
processes. Based upon the criteria listed in Section C.3, a panel of
scientific peers will evaluate the scientific and technical merits of proposals
received in response to this Announcement.

C.2.2 Proposal Details

C.2.2.1 Proposal Content

The proposal must include a standard Cover Page form, a General Form,
the scientific and technical justification (as described below), a
status page describing previously-awarded RXTE observations (see
below), a Target
Summary form, Target Forms as needed, and, optionally, Constraints Forms as
needed (see Appendix D). The information in the forms will be entered into a
data base that will be used in cataloguing and evaluating proposals. The forms
must be completed in the prescribed format. Cost sections should not be
submitted and will not be considered under this Announcement.

The abstract should be limited to 800 characters, including spaces between
words, with no embedded commands, i.e., flat ASCII only. Abstracts that exceed
this length will be truncated automatically at 800 characters when entered into
the data base. Abstracts and target lists for selected proposals will be made
available on publicly accessible data bases.

Proposers should also note that the pointing positions given in the Target Form
will be used to point the spacecraft and therefore should exercise
considerable care in specifying
these positions. Pointing errors can seriously degrade the data from an
observation. Positions must be stated in J2000 coordinates.

A target number should be assigned to each proposed pointing to designate the
priority of that particular pointing within an investigation requiring multiple
pointings. If it is necessary for the peer-review committee to reduce
observing times, an attempt will be made to preserve the highest priority
observations.

Proposers who have been awarded RXTE observing time in prior Cycles
should indicate the status of these programs. Proposers with RXTE programs
approved in Cycles 1 through 6 are required to append a page to
their proposal listing, by Cycle, proposal number and title, their
previously-accepted RXTE proposals and the status of the data analysis
or publications that have followed from them. Programs awarded to the
Principal Investigator and any major Co-Investigators should be included.

The discussion of the scientific investigation is limited to 4 (6) pages
including references, figures, and tables. It should provide the following
information, and be structured as follows:

(1) Scientific Problem. (Suggested text length: 2-3 pages.)
Clearly state the scientific problem to be
addressed, with relevant scientific background and references to previous work.
Show how the proposed RXTE observations and subsequent data analyses are
expected to address the problem and advance prior knowledge in the context of
past work in this research area. Justify the use of RXTE for the proposed
investigation by showing how the observations use the unique strengths and
capabilities of RXTE.

(2) Technical Feasibility. (Suggested text length: 1 page.)
Show how the requested observations
(exposure time, telemetry requirements, etc.) make possible the achievement of
the scientific objectives. State how targets or pointing locations were
selected. List assumptions about source intensity, surface brightness, and
spectrum. Estimates of both count rates and total counts needed to
successfully accomplish the
investigation must be provided. At a minimum, the Portable Interactive
Multi-Mission Simulator (PIMMS -
see the RXTE Technical Description)
should be used to estimate count rates. The spectral fitting
software XSPEC, or the online simulator
WebSpec, may also be used to
estimate count rates or demonstrate how the spectral data will be analyzed.
Timing simulations are strongly encouraged. Note that it is in the proposer's
best interest to provide enough detail to allow a reviewer to understand the
proposer's target brightness assumptions and to reproduce the count estimates.
The proposer should demonstrate that those estimated counts are sufficient to
extract the desired astrophysics from the observation. RXTE has numerous data
processing configurations and the user must select the configurations for the
on-board processing of the data stream for his or her proposed observations.
It is the proposer's responsibility to be knowledgeable of the configurations
and their limitations.

(3) Targets of Opportunity. Targets of Opportunity (TOO) may be
proposed. Proposers should state in their justification the estimated
probability that the TOO trigger will occur during the observing
period covered by this Announcement, and how they arrived at this
estimate. To simplify the proposal evaluation process, proposals
must not contain a mix of TOO and non-TOO targets.

(4) Constrained Observations. The proposer may desire to place constraints
(monitoring, coordination with observations at other wavelengths, uninterrupted,
etc.) on the proposed observations. A coordinated observation can be
designated for "special handling." However, this designation places increased
emphasis on matching the absolute coordinated schedule; a change in the
coordinated schedule can be accommodated up to 60 days in advance of the
observation. Up to 4 "special handling" requests per month will be considered,
so such constraints must be demonstrated as feasible and scientifically
justified.
The previously-available capability of performing alternate targets,
defined as a substitute for the primary target if the primary target
becomes scientifically uninteresting (e.g., becomes too faint), has
been discontinued due to the operational burden. Proposers should
also note the potential impact on time-constrained observations of an
interruption by a TOO.

(5) Justification of Telemetry Use. Requests for telemetry beyond the nominal
rates for each instrument must be justified due to the constrained nature of
this resource. Similarly, rates significantly below these allocations may be
viewed as an under-utilization of RXTE and should likewise
be justified. The allocated,
nominal rates are, assuming an observing efficiency of ~60%, ~40 kbits/s for
the PCA, and ~8 kbits/s for the HEXTE. The proposer is also invited to
discuss, within the page limit, possible uses of
increased telemetry if additional telemetry were to become available. In
particular, the proposer may specify the key parameter (temporal resolution,
spectral resolution, layer ID, etc.) to alter in the instrument configurations
if such an increase in telemetry were found to be feasible during his/her
observation.

(6) PCA Constraints. The PCA
is currently being operated with reduced duty cycles for three out of
the five PCU detectors. Proposers should calculate exposure
times and discuss technical feasibility with an expectation of using an
average of three PCUs. If special circumstances warrant or require the
use of four or five PCUs for an observation (e.g., faint source
spectroscopy or investigations of weak QPO signals), then a quantative
justification must be clearly stated in the Technical Feasibility
section. (Although every effort will be made to fulfill requests for
more than three PCUs, operational limitations make it impossible to
guarantee that the requested number of PCUs will be available.) In
addition, it should be noted that some observations, especially those
for source monitoring, may be conducted with two PCUs, and proposers
should discuss the expected impact of this limitation on their
observing program.

C.2.2.2 Page Restrictions, Certifications, and Quantity

As a result of the large number of proposals anticipated in response
to this Announcement, strict page limits will be enforced. The
scientific justification should consist of not more than four pages
(six for large programs; see C.1.1) where each side of a sheet of
paper with text or figures is considered a page. When printed out,
type should not be smaller than 10 point (standard typewriter size
print), and is limited to not more than 55 lines per page. Margins
should be a minimum of 1 inch on all sides. These pages and the
associated forms comprise the scientific proposal and should provide
the peer panel members with the essence of the proposed scientific
investigation.

Proposals should be submitted electronically. RPS submission of the
cover forms is still required. In addition, the cover forms and
scientific justifications should be submitted electronically as two
PostScript files. No hardcopies need be sent by postal mail. A full
step-by-step description of the electronic submission process can be
obtained from the relevant RXTE Web pages on Cycle 7 proposal submission.

Reviewers will consider only those pages in each proposal section that do
not exceed the page limits specified below.

All proposers must electronically submit their Cover Page,
General Form, Target Summary, Target Forms, and Constraints Forms.
Proposers who do not have access to electronic communications must
contact Dr. Smale at the above address no later than two weeks before
the submission deadline. Electronic submission facilitates efficient
proposal processing and reduces the likelihood of the introduction of
transcription errors into the proposal and observation databases. For
electronic forms submission, the RXTE Guest Observer Facility has made
available Remote Proposal Software (RPS) (see Appendix D). Additional
information on RPS is available from the
RXTE GOF web site at http://rxte.gsfc.nasa.gov/,

In addition, and new to Cycle 7, is the requirement that proposers
must also electronically submit their Forms as PostScript files, and
their scientific justification and associated materials as PostScript
files, as described in C.2.2.2 above.

C.3 Proposal Selection, Evaluation, and Implementation

C.3.1 Evaluation Criteria

The following criteria apply
to the evaluation of proposals submitted in response to this Announcement
and are
shown in descending order of priority.

The overall scientific merit of the investigation.

The suitability of using the RXTE observatory and data products for the
proposed investigation; the degree to which the investigation uses RXTE's
unique capabilities; the feasibility of accomplishing the objectives of the
investigation within the time, telemetry, and scheduling constraints; and the
feasibility of the analysis techniques.

The relevance of the proposed research to NASA's space science
program.

The competence and relevant experience of the Principal Investigator and
any collaborators as an indication of their ability to carry the investigation
to a successful conclusion. Past performance in scientific research,
including the use of RXTE data approved in prior Cycles, as
evidenced by the timely publication of articles in refereed scientific
journals, will be considered.

C.3.2 Proposal Selection

RXTE proposals will be evaluated by a scientific and technical review panel
convened by NASA. All proposals submitted in response to this Announcement and received
by the proposal deadline will be evaluated for scientific merit and for
technical feasibility with respect to spacecraft and observational constraints.
From experience with previous solicitations, a substantial oversubscription of
RXTE observing time and available telemetry is expected.

To aid in prioritizing investigations, proposals will be assigned a numerical
grade by the peer evaluation panel. Proposed observing programs must receive a
high ranking to be considered for selection. The detailed observing plan
(timeline) will be formulated and implemented by the SOC. It is the
intent of NASA that all selected observing programs be carried out,
although scheduling constraints and TOO observations may require
rescheduling some observations.

Proposers need not repropose if a selected observing
program is not carried out during the current observing period. Note
that in accordance with established RXTE policy, proposers of Cycle 6
TOO observations will be required to repropose their observing
programs if the TOO has not been carried out during the Cycle 6
period. Similarly, successful proposers of Cycle 7 TOO observations
will be required to repropose their observing programs if the TOO is
not carried out during Cycle 7.

Since RXTE has so many possible instrument configurations, and many of the
targets that RXTE will observe are expected to vary with time, it is expected
that individual targets may be observed many times without exhausting the
science that can be obtained. The peer evaluation panel will judge whether a
proposed observational program essentially duplicates one or more observations
made earlier, including those performed during the IOC period. The peer
evaluation panel may recommend that two or more proposals from different
investigators to observe the same source be scheduled, if the proposals have
sufficiently high scientific merit. Requests from an investigator to observe a
particular source more than once or to observe multiple sources with the same
scientific goal should generally be made in a single proposal. Separate
proposals to observe the same source more than once, each time with different
scientific goals, are acceptable if the goals could not be attained
simultaneously in a single observation. The acceptance of a scientific target
in previous cycles does not preclude it from being proposed (or reproposed) in
this cycle if the goals could not be attained with data currently in,
or anticipated to be in, the RXTE public data archive. Scientific
justification must be provided in each of the
situations described above.

While a balance between large, medium, and small observing programs is
still sought, the trend towards larger observing programs is
encouraged.

C.3.3 Implementation of Approved Observing Programs

All approved targets will be placed into an observation database. Each
observation will be assigned a unique identifying number. It is the
responsibility of the RXTE mission planning and operations team at the RXTE
Science Operations Facility (SOF) to produce a mission timeline out of all
approved observation requests. The process of mission timeline generation is
split into two parts: first, for the entire period covered by this
Announcement, a
long-term mission timeline (LMTL) will be generated with a precision of about a
week. Additional LMTL's will be generated in response to TOO's and other
timeline changes as necessary. Second, about three weeks prior to the
execution of the observations, a short-term mission timeline (SMTL) will be
produced on the basis of the LMTL. The SMTL is used for the automatic
generation of the required spacecraft commands. It will be optimized a final
time approximately one week prior to the start of a particular observation.

Targets are scheduled in the LMTL to achieve maximum efficiency in the
observing program within the operational constraints of RXTE. Unconstrained
observations are thus scheduled to produce the highest observing efficiency.
Any observation requiring time constraints will be designated as "time
critical" and its priority in scheduling will be related to its peer review
grade.

The SOF will make its best effort to schedule all approved observations. All
observations that are not scheduled or that were scheduled but not successfully
executed for whatever reason will automatically be rescheduled within the
current observing cycle. Approved non-TOO observations will be carried over into
the observing program of the next observing cycle. Approved TOO observations
will not be carried into the next observing cycle.

If observations are cut short by mission timeline optimization or other
constraints, a completion criterion will determine whether a given target
is scheduled for additional observing time. The completion criterion for each
requested pointing with RXTE is 80% of the recommended exposure time,
regardless of the grade assigned to the corresponding proposal by the peer
evaluation panel.

Any constraint on the scheduling of observations must be stated and justified.
SAA passage and Earth occultation will, of course, interrupt the average
observation. Long observations of low telemetry usage will likely be
interspersed with high telemetry rate, short observations. Observers who
desire uninterrupted observations may set the "uninterrupted" constraint flag,
but must justify the scientific necessity and must show that the observation is
feasible.

Users should also note that a prime purpose of RXTE is the capability to
respond to Targets of Opportunity (TOO's). Any observation may be interrupted
by a TOO. The priority grade assigned to a target will indicate the
susceptibility to interruption likely for that target. High-priority,
time-critical targets will have the least chance of interruption by a TOO (but
still not zero). Interrupted observations will be completed at a later time.
Note that proposers are not permitted to propose a TOO that would be triggered
by PCA or HEXTE data that is proprietary to another observer. They may,
however, propose a TOO that may be triggered by PCA or HEXTE slew data, by RXTE
ASM or BATSE data, or other means.

Investigators whose proposals are selected will receive the resulting
data in a form suitable for analysis. Twelve months after this
receipt, the data will be placed in the public domain via the RXTE
data archive.

C.4 Schedule

The current schedule for the review and selection of proposals for the sixth
observing cycle on RXTE is listed below. Note that the dates of events planned
beyond the Proposal Due Date are estimates and subject to change.

DateAction

June 18, 2001 Release of this Announcement

September 17, 2001 Proposals Due

Late 2001 Review; scheduling commences

March 1, 2002 Begin Cycle 7 Observations

Proposals may be submitted at any time during the period prior to the Proposal
Due Date. Proposals received after the due date will not be reviewed
during the current opportunity, but will be held for the next
review cycle at the request of the proposer.